The present invention relates generally to agricultural implements and, more particularly, to a marker assembly for use with an agricultural implement and having a float feature that allows limited vertical displacement of the marker assembly to accommodate variations in ground contours.
Agricultural seeders, which are commonly used to deposit seed, fertilizer, and granular chemicals onto a farm field, generally consist of a towable frame that supports one or more rows of seed units. Seed or other granular product is typically metered to the seed units which in turn deposit the product onto the farm field. The seeder will often include furrowing opening devices, such as coulters, knives, shanks, and the like that cut a furrow into the farm field immediately ahead of the seed units so that the granular product is deposited into a furrow rather than simply atop the farm field. A trailing packer will then pack the furrow to improve germination and/or fertilization.
Agricultural seeders are also commonly outfitted with a pair of marker assemblies. Each marker assembly will generally include a marker frame which carries a marking disc. A seeder will typically have a marker frame extending laterally on opposite sides of the seeder, and the marker frames can be independently raised and lowered by a respective lift assembly, such as a hydraulic cylinder. The marking disc is designed to cut a furrow into the farm field which serves as a marker as to the position of the seeder as the field was passed. Thus, during a subsequent pass of the farm field, the operator can position the seeder so that the next pass is properly aligned with the previous seeding pass to prevent overseeding of a previously seeded area or to prevent undesirable gaps in the seeded rows. Improper uniformity in spacing of the rows as well as distribution of the seed can negatively impact crop yields.
Occasionally, as the seeder is being towed by the tractor across the farm field, the marker frame may collide with an obstacle in the farm field, such as an unseen rock. To reduce the impact of such collisions, the marker frame must be built in a manner and with materials that are capable of withstanding the impact with such objects without causing fracture or other damage to the marker frame. Moreover, since the marker frame is coupled to the main frame of the seeder, the composition of the marker frame must be such that collision of the marker frame with an obstruction does not negatively impact the main towable frame of the seeder. This typically results in relatively heavy, bulky, and ultimately costly marker frames that can significantly impact the overall weight and size of the seeder as well as its cost.
In addition, it is not uncommon for the marker assembly to be towed along undulating terrain. This can be particularly pronounced for wider marker assemblies. Thus, marker assemblies are generally designed and constructed with sufficient flexibility to account for the expected range of ground contours. However, this flexibility can present issues in managing deployment of the marker assembly from a retracted stow position to an extended working position.
Therefore, there is a need for a marker assembly better suited to handle surface contours as well as collisions with field obstructions.